Two-magnon Raman scattering and pseudospin-lattice interactions in Sr2IrO4 and Sr3Ir2O7

Abstract

We have used Raman scattering to investigate the magnetic excitations and lattice dynamics in the prototypical spin-orbit Mott insulators Sr2IrO4 and Sr3Ir2O7. Both compounds exhibit pronounced two-magnon Raman scattering features with different energies, lineshapes, and temperature dependencies, which in part reflect the different influence of long-range frustrating exchange interactions. Additionally, we find strong Fano asymmetries in the lineshapes of low-energy phonon modes in both compounds, which disappear upon cooling below the antiferromagnetic ordering temperatures. These unusual phonon anomalies indicate that the spin-orbit coupling in Mott-insulating iridates is not sufficiently strong to quench the orbital dynamics in the paramagnetic state.

arXiv comment5 pages, 3 figures, submitted

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Cited by in corpus (46)

• The Challenge of Spin-Orbit-Tuned Ground States in Iridates
• Square Lattice Iridates
• Persistent paramagnons deep in the metallic phase of Sr${}_{2-x}$La${}_x$IrO${}_4$
• Pseudo Jahn-Teller Effect and Magnetoelastic Coupling in Spin-Orbit Mott Insulators
• High-Field Quantum Disordered State in $\alpha$-RuCl3: Spin Flips, Bound States, and a Multi-Particle Continuum
• The range of non-Kitaev terms and fractional particles in RuCl${}_3$
• A charge density wave-like instability in a doped spin-orbit-assisted weak Mott insulator
• Chiral Spin Mode on the Surface of a Topological Insulator
• Strain-engineering of the charge and spin-orbital interactions in Sr2IrO4
• Raman scattering study of vibrational and magnetic excitations in Sr${}_{2-x}$La${}_x$IrO${}_4$
• Strong Pseudospin-Lattice Coupling in Sr3Ir2O7: Coherent Phonon Anomaly and Negative Thermal Expansion
• Dispersive Magnetic and Electronic Excitations in Iridate Perovskites Probed with Oxygen $K$-Edge Resonant Inelastic X-ray Scattering
• Doping Evolution of Magnetic Order and Magnetic Excitations in (Sr${}_{1-x}$La${}_x$)${}_3$Ir${}_2$O${}_7$
• Coupling of lattice, spin and intra-configurational excitations of Eu3+ in Eu2ZnIrO6
• First-order structural transition and pressure-induced lattice/phonon anomalies in Sr${}_2$IrO${}_4$
• Quantum spin nematic phase in a square-lattice iridate
• Antiferromagnetic Excitonic Insulator State in Sr3Ir2O7
• Raman scattering from current-stabilized nonequilibrium phases in Ca${}_2$RuO${}_4$
• A Hubbard exciton fluid in a photo-doped antiferromagnetic Mott insulator
• Lattice frustration in spin-orbit Mott insulator Sr3Ir2O7 at high pressure
• Magnetic excitations and amplitude fluctuations in insulating cuprates
• Compressive-strain induced enhancement of exchange interactions and short-range magnetic order in Sr${}_2$IrO${}_4$ investigated by Raman spectroscopy
• Nanoscale Sr${}_2$IrO${}_4$ Freestanding Thin-Films for Flexible Electronics
• Magnetic and electronic ordering phenomena in the [Ru${}_2$O${}_6$] honeycomb lattice compound AgRuO${}_3$
• Raman scattering study of lattice and magnetic excitations in CrAs
• Orbiton-Phonon coupling in Ir5+(5d4) double perovskite Ba2YIrO6
• Symmetry-resolved two-magnon excitations in a strong spin-orbit-coupled bilayer antiferromagnet
• Isospin-phonon coupling and Fano-interference in spin-orbit Mott insulator Sr2IrO4
• Lattice dynamics and structural transition of the hyperhoneycomb iridate $\beta$-Li${}_2$IrO${}_3$ investigated by high-pressure Raman scattering
• Correlated Paramagnetism and Interplay of Magnetic and Phononic Degrees of Freedom in 3d-5d Coupled La2CuIrO6
• Spinons and damped phonons in spin-1/2 quantum-liquid Ba${}_4$Ir${}_3$O${}_{10}$ observed by Raman scattering
• Non-thermal breaking of magnetic order via photo-generated spin defects
• Signatures of non-Loudon-Fleury Raman scattering in the Kitaev magnet $\beta$-Li${}_2$IrO${}_3$
• Momentum-resolved lattice dynamics of parent and electron-doped Sr${}_2$IrO${}_4$
• Single crystal growth of iridates without platinum impurities
• Linear scaling relationship of Néel temperature and dominant magnons in pyrochlore ruthenates
• Polarized Raman spectroscopy study of metallic $(S{r}_{1-x}L{a}_x{)}_{3}I{r}_2{O}_7$: a consistent picture of disorder-interrupted unidirectional charge order
• Observation of excitons bound by antiferromagnetic correlations
• Critical fluctuations in the spin-orbit Mott insulator Sr${}_3$Ir${}_2$O${}_7$
• Quantum Criticality in a Layered Iridate
• Magneto-synthesis effect on magnetic order, phonons, and magnons in single-crystal Sr${}_2$IrO${}_4$
• A $j_{\mathrm{eff}}=1/2$ pseudospinon continuum in CaIrO${}_3$
• Potential of Raman scattering in probing magnetic excitations and their coupling to lattice dynamics
• Absence of temperature-dependent phonon anomalies in Sr2IrO4 and Sr3Ir2O7
• Phase coexistence and negative thermal expansion in the triple perovskite iridate Ba${}_3$CoIr${}_2$O${}_9$
• Non-Loudon-Fleury Raman scattering in spin-orbit coupled Mott insulators